A Master Fermenter Reveals Her Secrets to Kimchi Mastery

Han Oak, the renowned Korean restaurant in Northeast Portland famous for its crispy fried chicken, exquisite dumplings, and seasonal vegetable banchan, offers a welcoming atmosphere for solo diners. Here, you’re part of the family. (Need proof? Check out the Pacific Northwest episode of Dinogo’s Guide to the World, currently streaming on Hulu.) Until just before the pandemic, owners Peter Cho and Sun Young Park lived in a cozy apartment within the restaurant, just off the hallway near the restroom. Their children, Frankie and Elliot, often roam the space while Cho cooks and Park greets patrons; occasionally, Cho will scoop up a toddler and visit tables. Myung Ja Cho, Cho’s mother, still prepares the restaurant’s signature napa cabbage kimchi, a beloved item on the menu of banchan, the selection of small dishes perfect for snacking alongside your meal.

The elder Cho has been perfecting her recipe over her 71 years. As a child on the Korean island of Jeju-do, she learned the art of kimchi-making from her grandmother. Throughout the years, she gathered techniques from friends and family, and even now, she wonders if it’s truly perfect. “I’m never finished,” she reflects. Regardless, people travel from far and wide to taste her kimchi, whether it’s tucked inside mandu or simply served on a white plate.

Today, Myung Ja Cho views her kimchi recipe as a living entity: the salt quantity, brining duration for the cabbage, and fermentation time all change based on the season and the temperature during preparation. While we can’t disclose her precise recipe, she offers some transferable secrets to help those eager to embark on their own culinary journey.

Step 1: Choose the right ingredients (at the right season)

There are countless varieties of kimchi, made from ingredients like cucumbers and perilla leaves. The two types Myung Ja Cho prepares at Han Oak are baechu kimchi, which mainly features napa cabbage, and kkakdugi, crafted from mu, a large white Korean radish. The following guidance emphasizes baechu, primarily consisting of napa cabbage leaves but can also include julienned mu for added texture. Myung Ja Cho recommends preparing this in mid-fall to winter when both cabbage and radishes are at their freshest.

What to look for:

• Cabbage: When selecting a cabbage, choose one with bright green leaf tips; avoid those that appear pale or white. The leaves should be tight, firm, and thin, rather than loose, soft, and floppy. When sliced open, it should reveal a vibrant yellow interior. A robust cabbage will ensure the leaves remain crunchy after fermentation.
• Radish: Opt for a large, plump radish that is white and yellow at the bottom, transitioning to bright green near the stem and leaves. Selecting a radish is akin to choosing a watermelon — it should feel heavier than other radishes of similar size, indicating high water content. A light radish is likely overripe and dried out.
• Gochugaru: Gochugaru is ground Korean red pepper, essential for the flavor and mild heat of kimchi. Myung Ja Cho is a gochugaru enthusiast — her sisters in South Korea send her gochugaru from local farms. She insists that South Korean gochugaru is the finest option, as the sun-drying process of their chiles yields a richer, more complex flavor. If you can’t find Korean sun-dried gochugaru at your local store, you can order it online.

Step 2: Brining Time

Salting the cabbage is crucial for both the preservation and flavoring of the kimchi. The duration for which you let it soak in the saltwater brine depends on your local climate and the saltiness of the water. In a warm, air-conditioned-free environment like California, it’s best to brine for about six to seven hours; in a cooler kitchen, four to five hours may suffice. You’ll know it’s ready when the leaves begin to look slightly limp. The amount of salt varies based on the quantity of cabbage, but Cho suggests using the minimum amount necessary for safe fermentation — roughly 3 percent salt to water weight, akin to ocean water. While Cho prefers Korean coarse sea salt, regular sea salt can work as a substitute. After salting the cabbage, prepare your radish by trimming, slicing thinly, and washing it before tossing it into a dry salt brine.

Step 3: Prepare Your Marinade

While your ingredients are brining, prepare your marinade. The precise measurements and ratios depend largely on personal taste (hint: keep tasting!), but there are some essential components to include:

• First, a liquid to enhance the mix: Rather than plain water, Myung Ja Cho opts for dashi or vegetable broth to add richness to the kimchi marinade.
• Create a rice slurry: Combine your dashi with rice flour and bring it to a boil; it should become nicely thick. This helps the marinade adhere to the cabbage. The kimchi marinade shouldn’t be too thick; set aside extra broth to adjust the consistency later. Myung Ja Cho adds gochugaru to the warm rice slurry, allowing it to bloom beautifully.
• Incorporate ginger and alliums: Garlic, onion, and scallions are key aromatics in many Korean dishes, including kimchi. Roughly chop some onions, thinly slice ginger, and peel plenty of garlic — all these ingredients will go into a blender. Now is also a good time to slice scallions, which will be added to your kimchi at the very end.
• Add a touch of sweetness: Grated Asian pear or apple adds a hint of sweetness to the kimchi, though some prefer to use sugar. Others might combine all three — consider how sweet you want your kimchi to be. Remember the sweetness of your cabbage and radish; if they’re in season, they might contribute a lot, making extra sugar less necessary.
• Introduce a fishy flavor: Fish products, such as fermented salted shrimp or fish sauce, provide that distinctive kimchi flavor. Cho uses a blend of fish sauces, including Korean Canary fish sauce, adjusting to her taste preferences.

Blend your onion, pear, apple, garlic, and ginger with a splash of dashi or broth in a blender or food processor. In another bowl, mix the slurry, fish sauce, and gochugaru. Combine both mixtures, and voilà — you have your marinade. Cho suggests aiming for a saucy, smooth texture that’s not overly thin. Taste and adjust as needed: if it’s too fishy, add a bit more pear, or vice versa. Keep in mind that as the mixture ages, the tanginess will grow, while the fishiness will soften.

Step 4: Rinse and Mix

Before blending the marinade with your vegetables, it’s essential to rinse off the salt from the cabbage thoroughly. Cho rinses it twice and allows as much water to drain as possible. There's no need to rinse the radishes; they’re ready to use as soon as they’re drained from the brine. Once both the cabbage and radishes are prepared, combine them with the marinade. Additional ingredients you might consider adding include scallions, mustard leaves, green onions, or Korean chives known as buchu.

Step 5: Let it Sit (or Enjoy Now)

If you prefer your kimchi salty and less tangy, feel free to dig in right away. However, for those who enjoy a funky and acidic flavor profile, pack the cabbage into a jar (fermenting jars are ideal as they allow gas to escape while keeping out unwanted bacteria), seal it, and place it in a cool, dark spot. A dedicated kimchi fridge is perfect for serious kimchi lovers, but a cool corner of your kitchen works just as well.

Cho notes that the fermentation time ultimately depends on the outside temperature and how intense you want the kimchi's flavor. On warmer days, fermentation can start within 12 to 24 hours, while cooler conditions may extend it to two to three days. You’ll know it’s ready when you see small bubbles rising inside the jar. It will continue to ferment slowly and safely in the fridge. (Pro tip from Dinogo LA editor Matt Kang of K-Town fame: If you want to avoid a kimchi smell permeating your fridge, wrap the jar tightly in a plastic bag.) The timing and method of enjoying your kimchi are up to you — lightly fermented kimchis (a few weeks old) are excellent for cold dishes or enjoyed on their own, while more heavily fermented versions (up to three months) are perfect for soups and stews like kimchi jjigae.

Step 6: Enjoy it everywhere!

Jal meokkesseumnida! (In other words, get ready for a delicious meal.)